Holy Girls Apocalypse: Death Pair

The protagonist, Momozono Kuina, is a second-year middle school student. She perceives reality as a world steeped in filth, oppression, and absurdity, harboring an unspoken hatred she cannot express. Her only friend who sticks by her is Juhachi no Moa. Moara is a radio girl who stands on the school rooftop every morning, shouting incoherent rants through a megaphone. When these two, shut off from the world, face despair too great to bear, the story begins to shift dramatically.

https://www.cmoa.jp/title/329299/